Compounds and methods for the treatment of cardiovascular, inflammatory and immune disorders

ABSTRACT

Disubstituted tetrahydrofurans, tetrahydrothiophenes, pyrrolidines and cyclopentanes are disclosed that reduce the chemotaxis and respiratory burst leading to the formation of damaging oxygen radicals of polymorphonuclear leukocytes during an inflammatory or immune response. The compounds exhibit this biological activity by acting as PAF receptor antagonists, by inhibiting the enzyme 5-lipoxygenase, or by exhibiting dual activity, i. e., by acting as both a PAF receptor antagonist and inhibitor of 5-lipoxygenase. 
     A method to treat disorders mediated by PAF and/or leukotrienes is also disclosed, that includes administering an effective amount of one or more of the above-identified compounds or a pharmaceutically acceptable salt thereof, optionally in a pharmaceutically acceptable carrier.

FIELD OF THE INVENTION

This invention is in the area of 2,5-disubstituted tetrahydrothiophenes,tetrahydrofurans, pyrrolidines and 1,3-disubstituted cyclopentanes. Thecompounds exhibit biological activity by acting as PAF receptorantagonists, by inhibiting the enzyme 5-lipoxygenase, or by exhibitingdual activity, i. e., by acting as both a PAF receptor antagonist andinhibitor of 5-lipoxygenase.

BACKGROUND OF THE INVENTION

Platelet activating factor (PAF,1-O-alkyl-2-acetyl-sn-glycerol-3-phosphorylcholine) is a potentinflammatory phospholipid mediator with a wide variety of biologicalactivities. PAF was initially identified as a water soluble compoundreleased by immunoglobulin E (IgE)-sensitized rabbit basophils. It isnow known that PAF is also generated and released by monocytes,macrophages, polymorphonuclear leukocytes (PMNs), eosinophils,neutrophils, natural killer lymphocytes, platelets and endothelialcells, as well as by renal and cardiac tissues under appropriateimmunological and non-immunological stimulation. (Hwang, "Specificreceptors of platelet-activating factor, receptor heterogeneity, andsignal transduction mechanisms", Journal of Lipid Mediators 2, 123(1990)). PAF causes the aggregation and degranulation of platelets atvery low concentrations. The potency (active at 10⁻¹² to 10⁻⁹ M), tissuelevel (picomoles) and short plasma half life (2-4 minutes) of PAF aresimilar to those of other lipid mediators such as thromboxane A₂,prostaglandins, and leukotrienes.

PAF mediates biological responses by binding to specific PAF receptorsfound in a wide variety of cells and tissues. Structure-activity studieson PAF and its analogs indicate that the ability of PAF to bind to thesereceptors is structure specific and stereospecific. (Shen, et al., "TheChemical and Biological Properties of PAF Agonists, Antagonists, andBiosynthetic Inhibitors", Platelet-Activating Factor and Related LipidMediators, F. Snyder, Ed. Plenum Press, New York, N.Y. 153 (1987)).

While PAF mediates essential biological responses, it also appears toplay a role in pathological immune and inflammatory responses. Manypublished studies have provided evidence for the involvement of PAF inhuman diseases, including arthritis, acute inflammation, asthma,endotoxic shock, pain, psoriasis, ophthalmic inflammation, ischemia,gastrointestinal ulceration, myocardial infarction, inflammatory boweldiseases, and acute respiratory distress syndrome. Animal models alsodemonstrate that PAF is produced or increased in certain pathologicalstates.

The involvement of PAF in pathological inflammatory and immune stateshas stimulated a substantial research effort to identify PAF receptorantagonists. In 1983, a phospholipid analog referred to as CV-3988(rac-3-(N-n-octadecyl-carbamoyloxy-ω-methoxypropyl-2-thiazolioethylphosphate) was reported to have PAF receptor antagonist properties.(Terashita, et al., Life Sciences 32, 1975 (1983).) In other early workin this area, Shen, et al., (in Proc. Natl. Acad. Sci. (U.S.A.) 82, 672(1985)), reported that kadsurenone, a neolignan derivative isolated fromPiper futokadsura Sieb et Zucc (a Chinese herbal plant) was a potent,specific and competitive inhibitor of PAF activity at the receptorlevel.

Hwang, et al., disclosed in 1985 thattrans-2,5-bis-(3,4,5-trimethoxyphenyl) tetrahydrofuran (L-652, 731)inhibits the binding of tritiated PAF to PAF receptor sites. (Hwang, etal., "Trans-2,5-bis-(3,4,5-trimethoxyphenyl)tetrahydrofuran", Journal ofBiological Chemistry 260, 15639 (1985).) L-652,731 was found to beorally active, and to inhibit PAF-induced rat cutaneous vascularpermeability at a dosage of 30 mg/kg body weight. The compound was foundto have no effect on the enzyme 5-lipoxygenase. Hwang, et al. alsoreported that trans-L-652,731 (wherein the aryl groups at the 2 and 5positions are on opposite sides of the plane of the tetrahydrofuranring) is approximately 1000 times more potent than cis-L-652,731(wherein the 2 and 5 aryl substituents are on the same side of the planeof the tetrahydrofuran ring).

In 1988, Hwang, et al., reported that L-659,989(trans-2-(3-methoxy-4-propoxyphenyl-5-methylsulfonyl)-5-(3,4,5-trimethoxyphenyl)tetrahydrofuran)is an orally active, potent, competitive PAF receptor antagonist, withan equilibrium inhibition constant 10 times greater than that oftrans-L-652,731. (Hwang, et al., J. Pharmacol. Ther. 246, 534 (1988).)

U.S. Pat. Nos. 4,996,203, 5,001,123 and 4,539,332 to Biftu, et al. andEuropean Patent Application Nos. 89202593.3, 90306235.4, and 90306234.7disclose that specific classes of 2,5-diaryl tetrahydrofurans are PAFreceptor antagonists.

Bowles et al., Synlett, 1993, pp 111 disclose a limited number ofsubstituted tetrahydrofurans which may possess PAF receptor antagonism.

Danyoshi et al., Chem. Pharm. Bull., 1989, pp 1969, disclose2-substituted-N-alkoxycarbonyl pyrrolidines which inhibit PAF inducedrabbit platelet aggregation.

Leukotrienes, like PAF, are potent Local mediators, playing a major rolein inflammatory and allergic responses, including arthritis, asthma,psoriasis, and thrombotic disease. Leukotrienes are straight chaineicosano:ids produced by the oxidation of arachidonic acid bylipoxygenases. Arachidonic acid is oxidized by 5-lipoxygenase to thehydroperoxide 5-hydroperoxyeicosatetraenoic acid (5-HPETE), that isconverted to leukotriene A₄, that in turn can be converted toleukotriene B₄, C₄, or D₄. The slow-reacting substance of anaphylaxis isnow known to be a mixture of leukotrienes C₄, D₄, and E₄, all of whichare potent bronchoconstrictors. There has been a research effort todevelop specific receptor antagonists or inhibitors of leukotrienebiosynthesis, to prevent or minimize pathogenic inflammatory responsesmediated by these compounds.

Leukotrienes are released simultaneously from leukocytes with PAF,possibly from a common phospholipid precursor such as1-O-hexadecyl-2-arachidonyl-sn-glycero-phosphocholine, and upon cellularactivation, act synergistically with PAF in many biological models.European Patent Application Nos. 90117171.0 and 901170171.0 discloseindole, benzofuran, and benzothiophene lipoxygenase inhibitingcompounds.

Recently, it was reported that the tetrahydrothiophene derivative ofL-652,731, trans-2,5-bis-(3,4,5-trimethoxyphenyl)tetrahydrothiophene(L-653,150), is a potent PAF antagonist and a moderate inhibitor of5-lipoxygenase. It has been disclosed that certain 2,5-diaryltetrahydrothiophenes are PAF antagonists and leukotriene synthesisinhibitors. (Biftu, et al., Abstr. of 6th Int. Conf. on Prostaglandinsand Related Compounds, Jun. 3-6, 1986, Florence, Italy; U.S. Pat. No.4,757,084 to Biftu); Wo 92/15294; WO 94/01430; WO 94/04537; and WO94/06790.

Given the significant number of pathological immune and inflammatoryresponses that are mediated by PAF and leukotrienes, there remains aneed to identify new compounds and compositions that exhibit PAFreceptor antagonistic activity or inhibit the enzyme 5-lipoxygenase.

Therefore, it is an object of the present invention to provide compoundsthat reduce the chemotaxis and respiratory burst leading to theformation of damaging oxygen radicals during an inflammatory or immuneresponse.

It is another object of the present invention to provide pharmaceuticalcompositions for the treatment of pathological immune or inflammatorydisorders mediated by PAF or products of 5-lipoxygenase.

It is another object of the present invention to provide a method forthe treatment of pathological immune or inflammatory disorders mediatedby PAF or products of 5-lipoxygenase.

SUMMARY OF THE INVENTION

Compounds of Formula I are provided ##STR1## wherein: Ar is an aryl orheteroaryl group that is optionally substituted, preferably with halo(including but not limited to fluoro), lower alkoxy (including methoxy),lower aryloxy (including phenoxy), W, cyano, or R³ ;

m is 0 or 1;

W is independently --AN(OM)C(O)N(R³)R⁴, --AN(R³)C(O)N(OM)R⁴,--AN(OM)C(O)R⁴, --AC(O)N(OM)R⁴, --C(O)N(OM)R⁴, --C(O)NHA, --A--B;

A is lower alkyl, lower alkenyl, lower alkynyl, alkaryl or aralkylgroups, wherein one or more carbons optionally can be replaced by O, N,or S, however, --Y--A-- should not include two adjacent heteroatoms(i.e., --O--O--, --S--S--, --O--S--, etc.);

B is selected from the group consisting of pyridylimidazole andbenzimidazole, either of which is optionally substituted with R₃, andwherein the pyridylimidazole or benzimidazole is preferably connected toA through a nitrogen atom;

M is hydrogen, a pharmaceutically acceptable cation, or a metabolicallycleavable leaving group;

X is O, S, S(O), NR⁵, or CHR⁵ ;

Y is O, S, S(O), NR⁵, or CHR⁵ ;

R¹ and R² are independently hydrogen, lower alkyl including methyl,cyclopropylmethyl, ethyl, isopropyl, butyl, pentyl hexyl, and C₃₋₈cycloalkyl, for example, cyclopentyl; halo lower alkyl, for example,trifluoromethyl; halo, for example fluoro; and --COOH;

R³ and R⁴ are independently hydrogen or alkyl, alkenyl, alkynyl, aryl,aralkyl, alkaryl, C₁₋₆ alkoxy-C₁₋₁₀ alkyl, C₁₋₆ alkylthio-C₁₋₁₀ alkyl,heteroaryl, or heteroarylalkyl-;

R⁵ is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, alkaryl,--AN(OM)C(O)N(R³)R⁴, --AN(R³)C(O)N(OM) R⁴, --AN(OM)C(O)R⁴,--AC(O)N(OM)R⁴, --AC(O)N(OM) R⁴, --AS(O)nR³, --AS(O)_(n) CH₂ C(O)R³,--AS(O)_(n) CH₂ CH(OH)R³, --AC(O)NHR³ ; and

wherein n is 0-2.

The Ar group, in one embodiment, is selected from the group consistingof phenyl, trimethoxyphenyl, climethoxyphenyl, fluorophenyl, andspecifically 4-fluorophenyl, difluorophenyl, pyridyl, dimethoxypyridyl,quinolinyl, furyl, imidazolyl, and thienyl groups.

In one embodiment, --A--B is ##STR2## and Ar is an optionallysubstituted aryl or heteroaryl group, as described in more detail insection I.A. below.

These compounds in general reduce the chemotaxis and respiratory burstleading to the formation of damaging oxygen radicals ofpolymorphonuclear leukocytes during an inflammatory or immune response.The compounds exhibit this biological activity by acting as PAF receptorantagonists, by inhibiting the enzyme 5-lipoxygenase, or by exhibitingdual activity, i.e., by acting as both a PAF receptor antagonist andinhibitor of 5-lipoxygenase.

Another embodiment of the present invention is a pharmaceuticalcomposition that includes an effective amount of a compound of Formula Ior its pharmaceutically acceptable salt or derivative in combinationwith a pharmaceutically acceptable carrier.

A method to treat disorders mediated by PAF or leukotrienes is alsodisclosed, that includes administering an effective amount of one ormore of the above-identified compounds or a pharmaceutically acceptablesalt or derivative thereof, optionally in a pharmaceutically acceptablecarrier.

Examples of immune, allergic and cardiovascular disorders includegeneral inflammation, cardiovascular disorders including hypertension,skeletal-muscular disorders, osteoarthritis, gout, asthma, lung edema,adult respiratory distress syndrome, pain, aggregation of platelets,shock, rheumatoid arthritis, juvenile rheumatoid arthritis, psoriaticarthritis, psoriasis, autoimmune uveitis, allergic encephalomyelitis,systemic lupus erythematosis, acute necrotizing hemorrhagicencephalopathy, idiopathic thrombocytopenia, polychondrilis, chronicactive hepatitis, idiopathic sprue, Crohn's disease, Gravesophthalmopathy, primary biliary cirrhosis, uveitis posterior,interstitial lung fibrosis; allergic asthma; and inappropriate allergicresponses to environmental stimuli such as poison ivy, pollen, insectstings and certain foods, including atopic dermatitis and contactdermatitis.

The compounds disclosed herein can also be used as research tools tostudy the structure and location of PAF receptors as well as biologicalpathways involving leukotrienes.

The following are nonlimiting examples of compounds that fall withinFormula I. These examples are merely exemplary, and are not intended tolimit the scope of the invention:

2-(3,4,5-trimethoxyphenyl)-5-3-(N'-methyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran;

2-(4-fluorophenyl)-5-3-(N'-methyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran;

2-(3,4,5-trimethoxyphenyl)-5-3-(N'-n-butyl-N'-hydroxyureidyl)-propoxy!tetrahydrofuran;

2-(4-fluorophenyl)-5-3-(N'-n-butyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran;

2-(3',4'-dimethoxyphenyl)-5-3-(N-butyl-N-hydroxyureidyl)!-propoxytetrahydrofuran;

2-(3',4'-dimethoxyphenyl)-5-3-(N-methyl-N-hydroxyureidyl)!-propoxytetrahydrofuran;

2-(2,4,5-trimethoxyphenyl)-5-(3-hydroxyureidylpropoxy)-tetrahydrofuran;

2-(4-fluorophenyl)-5-(3-hydroxyureidylpropoxy)tetrahydrofuran;

2-(4-fluorophenyl)-5-3-(N'-methyl-N'-hydroxyureidyl)propoxy!tetrahydrothiophene; and

2-(4-fluorophenyl)-5-(3-hydroxyureidylpropoxy)tetrahydrothiophene.

Further nonlimiting examples of other compounds that fall within FormulaI are set forth below in Tables 1 and 2.

                                      TABLE 1                                     __________________________________________________________________________     ##STR3##                                                                     Ar         X*       W                                                         __________________________________________________________________________     ##STR4##  O C      CH.sub.2 CH.sub.2 CH.sub.2 NHC(O)N(OH)CH.sub.3  SAME      SAME       S        SAME                                                      SAME       NH       SAME                                                      SAME       O        CH.sub.2 CH.sub.2 CH.sub.2 N(OH)C(O)NH.sub.2              SAME       C        SAME                                                      SAME       S        SAME                                                      SAME       NH       SAME                                                      SAME       O        CH.sub.2 CH.sub.2 CH.sub.2 N(OH)C(O)NHCH.sub.3            SAME       C        SAME                                                      SAME       O        CH.sub.2 CHCHCH.sub.2 N(OH)CONH.sub.2                      ##STR5##  SAME AS ABOVE                                                                          SAME AS ABOVE                                              ##STR6##  SAME AS ABOVE                                                                          SAME AS ABOVE                                              ##STR7##  SAME AS ABOVE                                                                          SAME AS ABOVE                                              ##STR8##  SAME AS ABOVE                                                                          SAME AS ABOVE                                              ##STR9##                                                                     __________________________________________________________________________     *C refers to CHR.sup.5. Y is O, CHR.sup.5, S, or NH.                     

                  TABLE 2                                                         ______________________________________                                         ##STR10##                                                                    Ar                W                                                           ______________________________________                                         ##STR11##                                                                                       ##STR12##                                                  same as above                                                                                    ##STR13##                                                  same as above                                                                                    ##STR14##                                                  same as above                                                                                    ##STR15##                                                   ##STR16##                                                                                       ##STR17##                                                  ______________________________________                                    

DETAILED DESCRIPTION OF THE INVENTION

I. Description and Synthesis of the Compounds

A. Compounds

The term alkyl, as used herein, unless otherwise specified, refers to asaturated straight, branched, or cyclic hydrocarbon of C₁ to C₁₀, andspecifically includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl,t-butyl, pentyl, cyclopentyl, isopentyl, neopentyl, hexyl, isohexyl,cyclohexyl, 3-methylpentyl, 2,2-dimethylbutyl, and 2,3-dimethylbutyl.The alkyl group can be optionally substituted with any appropriategroup, including but not limited to R³ or one or more moieties selectedfrom the group consisting of halo, hydroxyl, amino, alkylamino,arylamino, alkoxy, aryloxy, nitro, cyano, sulfonic acid, sulfate,phosphonic acid, phosphate, or phosphonate, either unprotected, orprotected as necessary, as known to those skilled in the art, forexample, as taught in Greene, et al., "Protective Groups in OrganicSynthesis," John Wiley and Sons, Second Edition, 1991.

The term halo, as used herein, refers to chloro, fluoro, iodo, or bromo.

The term lower alkyl, as used herein, and unless otherwise specified,refers to a C₁ to C₆ saturated straight, branched, or cyclic (in thecase of C₅₋₆) hydrocarbon, and specifically includes methyl, ethyl,propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, cyclopentyl,isopentyl, neopentyl, hexyl, isohexyl, cyclohexyl, 3-methylpentyl,2,2-dimethylbutyl, and 2,3-dimethylbutyl, optionally substituted asdescribed above for the alkyl groups.

The term alkenyl, as referred to herein, and unless otherwise specified,refers to a straight, branched, or cyclic (in the case of C₅₋₆)hydrocarbon of C₂ to C₁₀ with at least one double bond, optionallysubstituted as described above.

The term lower alkenyl, as referred to herein, and unless otherwisespecified, refers to an alkenyl group of C₂ to C₆, and specificallyincludes vinyl and allyl.

The term lower alkylamino refers to an amino group that has one or twolower alkyl substituents.

The term alkynyl, as referred to herein, and unless otherwise specified,refers to a C₂ to C₁₀ straight or branched hydrocarbon with at least onetriple bond, optionally substituted as described above. The term loweralkynyl, as referred to herein, and unless otherwise specified, refersto a C₂ to C₆ alkynyl group, specifically including acetylenyl andpropynyl.

The term aryl, as used herein, and unless otherwise specified, refers tophenyl, biphenyl, or napthyl, and preferably phenyl. The aryl group canbe optionally substituted with any suitable group, including but notlimited to one or more moieties selected from the group consisting ofhalo, hydroxyl, amino, alkylamino, arylamino, alkoxy, aryloxy, nitro,cyano, sulfonic acid, sulfate, phosphonic acid, phosphate, orphosphonate, either unprotected, or protected as necessary, as known tothose skilled in the art, for example, as taught in Greene, et al.,"Protective Groups in Organic Synthesis," John Wiley and Sons, SecondEdition, 1991, and preferably with halo (including but not limited tofluoro), lower alkoxy (including methoxy), lower aryloxy (includingphenoxy), W, cyano, or R³.

The term haloalkyl, haloalkenyl, or haloalkynyl refers to a alkyl,alkenyl, or alkynyl group in which at least one of the hydrogens in thegroup has been replaced with a halogen atom.

The term heteroaryl, heterocycle or heteroaromatic, as used herein,refers to an aromatic moiety that includes at least one sulfur, oxygen,or nitrogen in the aromatic ring, which can optionally be substituted asdescribed above for the aryl groups. Non-limiting examples are pyrryl,furyl, pyridyl, 1,2,4-thiadiazolyl, pyrimidyl, thienyl, isothiazolyl,imidazolyl, tetrazolyl, pyrazinyl, pyrimidyl, quinolyl, isoquinolyl,benzothienyl, isobenzofuryl, pyrazolyl, indolyl, purinyl, carbazolyl,benzimidazolyl, and isoxazolyl.

The term aralkyl refers to an aryl group with an alkyl substituent.

The term alkaryl refers to an alkyl group that has an aryl substituent.

The term organic or inorganic anion refers to an organic or inorganicmoiety that carries a negative charge and can be used as the negativeportion of a salt.

The term "pharmaceutically acceptable cation" refers to an organic orinorganic moiety that carries a positive charge and that can beadministered in association with a pharmaceutical agent, for example, asa countercation in a salt. Pharmaceutically acceptable cations are knownto those of skill in the art, and include but are not limited to sodium,potassium, and quaternary amine.

The term "metabolically cleavable leaving group" refers to a moiety thatcan be cleaved in vivo from the molecule to which it is attached, andincludes but is not limited to an organic or inorganic anion, apharmaceutically acceptable cation, acyl (for example (alkyl)C(O),including acetyl, propionyl, and butyryl), alkyl, phosphate, sulfate andsulfonate.

The term PAF receptor antagonist refers to a compound that binds to aPAF receptor with a binding constant of 30 μM or lower.

The term 5-lipoxygenase inhibitor refers to a compound that inhibits theenzyme at 30 μM or lower in a broken cell system.

The term pharmaceutically active derivative refers to any compound thatupon administration to the recipient, is capable of providing directlyor indirectly, the compounds disclosed herein.

The 2,5-disubstituted tetrahydrothiophenes, tetrahydrofurans andpyrrolidines, as well as the 1,3-disubstituted cyclopentanes describedherein exhibit PAF receptor antagonist activity or inhibit the enzyme5-lipoxygenase, or have dual activity, and are thus useful in thetreatment of humans who have immune allergic or cardiovascular disordersthat are mediated by PAF or products of 5-lipoxygenase.

B. Stereochemistry

The 2,5-disubstituted tetrahydrofurans, tetrahydrothiophenes, andpyrrolidines exhibit a number of stereochemical configurations. Carbonatoms 2 and 5 in the center ring are chiral, and thus the center ringexists at a minimum as a diastereomeric pair. Each diastereomer existsas a set of enantiomers. Therefore, based on the chiral C₂ and C₅ atomsalone, the compound is a mixture of four enantiomers.

If non-hydrogen substituents are located on carbon atoms 3 and 4 in thecenter ring, then the C₃ and C₄ atoms are also chiral, and can alsoexist as a diastereomeric pair, that is also a mixture of fourenantiomers.

The 1,3-cyclopentanes disclosed herein also exhibit a number ofstereochemical configurations. Carbon atoms 1 and 3 in the center ringare chiral, and thus the center ring exists at a minimum as adiastereomeric pair. Each diastereomer exists as a set of enantiomers.Therefore, based on the chiral C₁ and C₃ atoms alone, the compound is amixture of four enantiomers.

If non-hydrogen substituents are located on carbon atoms 4 and 5 in thecenter ring, then the C₄ and C₅ atoms are also chiral, and can alsoexist as a diastereomeric pair, that is also a mixture of fourenantiomers.

One of ordinary skill in the art can easily synthesize and separate theenantiomers of the disclosed compounds using chiral reagents and knownprocedures, and can evaluate the biological activity of the isolatedenantiomer using methods disclosed herein or otherwise known. Throughthe use of chiral NMR shift reagents, polarimetry, or chiral HPLC, theoptical enrichment of the compound can be determined.

Classical methods of resolution include a variety of physical andchemical techniques. Often the simplest and most efficient technique isrepeated recrystallization. Recrystallization can be performed at anystage in the preparation of the compound, or the final enantiomericproduct. If successful, this simple approach represents a method ofchoice.

When recrystallization fails to provide material of acceptable opticalpurity, other methods can be evaluated. If the compound is basic, onecan use chiral acids that form diastereomeric derivatives that maypossess significantly different solubility properties. Non-limitingexamples of chiral acids include malic acid, mandelic acid, dibenzoyltartaric acid, 3-bromocamphor-8-sulfonic acid, 10-camphorsulfonic acid,and di-p-toluoyltartaric acid. Similarly, acylation of a free hydroxylgroup with a chiral acid also results in the formation of diastereomericderivatives whose physical properties may differ sufficiently to permitseparation.

Enantiomerically pure or enriched compounds can be obtained by passingthe racemic mixture through a chromatographic column that has beendesigned for chiral separations.

C. Syntheses of Active Compounds

The 2,5-disubstituted tetrahydrofurans, tetrahydrothiophenes, andpyrrolidines disclosed herein can be prepared in a variety of ways knownto those skilled in the art, including by methods disclosed by Whittakeret al, Synlett, 1993 pp 111, Biorg. Med. Lett., 1993 pp 1499; Achiwa etal., Chem. Pharm. Bull., 1989, pp. 1969.

1,3-Disubstituted cyclopentanes can be prepared using the procedure ofGraham, et al. (1.3-Diaryl Cyclopentanes: A New Class of Potent PAFReceptor Antagonists. 197th ACS National Meeting, Dallas, Tex., Apr.9-14, 1989, Division of Medicinal Chemistry, poster no. 25 (abstract)),or by other known methods.

A general procedure for preparing a hydroxyurea is shown below in Scheme1: ##STR18##

General procedures for preparing reverse hydroxyureas are shown inScheme 2: ##STR19##

A general procedure for preparing a hydroxamic acid is shown in Scheme3: ##STR20##

A general procedure for preparing a :reverse hydroxamic acid is shown inScheme 4: ##STR21##

Scheme 5 shows the synthesis of 2-(3,4,5-trimethoxyphenyl)-5-3-(N'-substituted-N'-hydroxyureidyl)propoxy!tetrahydrofuran (1-4) and2-(4-fluorophenyl)-5-3-(N'-substituted-N'-hydroxyureidyl)propoxy!tetrahydrofuran (9-12):##STR22##

Scheme 6 shows the synthesis of2-(2,4,5-trimethoxyphenyl)-5-(3-hydroxyureidyl propoxy)tetrahydrofuran(13) and 2-(4-fluorophenyl)5-(3-hydroxyureidylprolpoxy)tetrahydrofuran(14,15) ##STR23##

Scheme 7 shows the synthesis of 2-(3,4-dimethoxyphenyl)-5-3-N'-substituted-N'-hydroxyureidyl propoxy!tetrahydrofuran (5-8):##STR24##

The following examples are merely illustrative, and not intended tolimit the scope of the invention.

EXAMPLE 1 Preparation of 2-(3,4,5-trimethoxyphenyl)-5-3-(N'-substituted-N'-hydroxyureidyl)propoxy!tetrahydrofuran (1-4) and2-(4-fluorophenyl)-5-3-(N'-substituted-N'-hydroxyureidyl)propoxy!tetrahydrofuran (9-12)

(a) Preparation of 4-(3,4,5-trimethoxyphenyl)-4-ketone-butyric acidt-butyl ester (compound 101)

3,4,5-Trimethoxybenzaldehyde (8.0 g, 40.77 mmol), tert-butyl acrylate(5.29 g, 41.29 mmol) and the catalyst3-ethyl-5-(2-hydroxyethyl)-4-methylthiazolium bromide (3.52 g, 13.95mmol) were dissolved in 50 mL dimethyl formamide (DMF). To this solutionwas added 5.86 mL triethylamine. The reaction mixture was stirred at 60°C. for 16 hours, cooled to room temperature and quenched by adding 10%HCl (PH 1-2), and extracted with dichioromethane. The organic layer waswashed with water and saturated NaCl solution, dried over MgSO₄,filtered and evaporated in vacuo to an oil. The product was purified bycolumn chromatography (silica, 3:1 hexane/ethyl acetate) (4.5 g, 34%). ¹H NMR (CDCl₃): 1.46(2,9H); 2.70(t,2H); 3.24(t,2H); 3.92(s,9H);7.25(s,2H).

(b) Preparation of 4-(4-fluorophenyl)-4-ketone-butyric acid t-butylester (compound 119)

This compound was prepared using a process similar to that set forth inExample 1(a), replacing the 3,4,5-trimethoxy-benzaldehyde with4-fluorobenzaldehyde. ¹ H NMR (CDCl₃): 1.45(s,9H); 2.70(t,2H);3.23(t,2H); 7.12(m,2H); 8.02(m,2H)

(c) Preparation of 4-(3,4,5-trimethoxyphenyl)-4-hydroxy-butyric acidt-butyl ester (compound 102)

The ketone ester 101 (1.09 g, 3.36 mmol) was added to 10 mL THF and 20mL methanol. An aqueous solution of NaBH₄ (127.3 mg, 3.36 mmol in 5 mLwater) was added to this mixture in a dropwise manner at 0° C. Thereaction mixture was stirred at room temperature for 4 hours, quenchedwith water and extracted with ethyl acetate. The organic layer waswashed with water, saturated NaCl solution, dried over MgSO₄ filteredand evaporated in vacuo to provide the product (1.13 g, 103%). ¹ H NMR(CDCl₃): 1.46(s,9H); 2.02(m,2H); 2.37(t,2H); 3.84(s,3H); 3.88(s,6H);4.70(m,1H); 6.58(s,2H).

(d) Preparation of 4-(4-fluorophenyl)-4-hydroxy-butyric acid t-butylester (compound 120)

This compound was prepared from 119 using a procedure similar to thatset forth in Example 1(c), replacing compound 101 with compound 119. ¹ HNMR (CDCl₃): 1.44(s,9H); 2.00(m,2H); 2.32(m,2H); 4.72(m,1H); 7.01(m,2H);7.30(m,2H).

(e) Preparation of 4-(3,4,5-trimethoxyphenyl)-δ-lactone (compound 104)

The hydroxy ester 102 (1.13 g, 3.47 mmol) was added to 4 mL methanol,1.5 mL water and 5M aqueous sodium hydroxide solution (4.5 mL). Thereaction mixture was stirred at room temperature for 30 minutes and then12 mL of saturated aqueous NaHCO₃ solution was added. The aqueous phasewas washed with ether, acidified to pH 1-2 by adding conc. HCl, andextracted with benzene (2×30 mL). The benzene layer was checked by TLCwhich showed that some of the lactone has been formed. PPTS (10 mg) wasadded to the benzene extract and the mixture was refluxed for 1 hour toremove water. The reaction mixture was washed with saturated NaHCO₃solution and evaporated in vacuo to provide the desired lactone as asolid (700 mg, 80%). ¹ H NMR (CDCl₃): 2.20(m,1H); 2.68(m,3H);3.85(s,3H); 3.88(s,6H); 5.46(m,1H); 6.55(s,2H).

(f) Preparation of 4-(4-fluorophenyl)-δ-lactone (compound 122)

This compound was prepared from 120 using a procedure similar to thatset forth in Example 1(e), replacing compound 102 with compound 120. ¹ HNMR (CDCl₃): 2.20(m,1H); 2.68(m,3H); 5.50(m,1H); 7.10(t,2H); 7.32(m,2H).

(g) Preparation of 2-(3,4,5-trimethoxyphenyl)-5-hydroxy-tetrahydrofuran(105)

Lactone 104 (6.86 g, 27.22 mmol) was dissolved in dry toluene (100 mL)and the solution was cooled to -70° C. A 1.5M toluene solution of DIBALH(28 mL) was added to the solution in a dropwise manner. The reactionmixture was stirred at -70° C. for 1 hour. The reaction was quenchedthrough the addition of methanol (11 mL) while maintaining a temperatureof <-60° C. The mixture was warmed to -20° C. followed by the additionof saturated aqueous potassium sodium tartrate solution (96 mL) whilethe reaction temperature was maintained between -10 and 0° C. Thereaction mixture was stirred at 0° C. for 3 hours and then the twophases were separated. The aqueous layer was extracted with ethylacetate. The combined organic layers were washed with water, saturatedNaCl solution, and then concentrated in vacuo to afford the product(6.51 g, 94%). ¹ H NMR (CDCl₃): 1.82-2.48(m,4H); 3.84(s,3H); 3.88(s,6H);4.97, 5.20(m,1H); 5.65, 5.79(m,1H); 6.56, 6.70(s,2H).

(h) Preparation of 2-(4-fluorophenyl)-5-hydroxy-tetrahydrofuran (123)

This compound was prepared from 122 using a procedure similar to thatset forth in Example 1(g), replacing compound 104 with compound 122. ¹ HNMR (CDCl₃): 1.79(m,1H); 1.95-2.10(m,1H); 2.20-2.32(m,1H); 2.48(m,1H);5.00 & 5.22(m,1H); 5.63 & 5.78(m,1H); 7.04(m,2H); 7.30 & 7.41(m,2H).

(i) Preparation of trans and cis2-(3,4,5-trimethoxyphenyl)-5-(3-phthalimidyl propoxy)tetrahydrofuran(compounds 107, 108)

Compound 105 (1.14 g, 4.49 mmol) was dissolved in 4 mL dichloromethane.Triethylamine (681.4 mg, 6.73 mmol) was added to this solution. Thereaction mixture was cooled with an ice bath and trifluoroaceticanhydride (1.41 g, 6.73 mmol) was added in a dropwise manner. Thereaction mixture was stirred at 0° C. for 30 minutes and then3-phthalimidylpropanol (106) (2.4 g, 13.26 mmol) was added. The reactionmixture was warmed to room temperature and stirred at room temperaturefor 2 hours. The reaction was quenched with saturated aqueous NaHCO₃solution and extracted with ethyl acetate. The organic layer was washedwith water and saturated NaCl solution, dried over MgSO₄, filtered andevaporated in vacuo to an oil which was purified by columnchromatography (silica, 2:1 hexane/ethyl acetate) (107: 522 mg (trans);108: 271 mg (cis); 1:1 mixture of 107 and 108: 110 mg; total yield 46%).¹ H NMR (CDCl₃): 107: 1.70(m,1H); 1.82(m,1H); 2.00(m,2H); 2.02(m,1H);2.28(m,1H); 3.46(m,1H); 3.83(s,3H); 3.84(m,3H); 3.88(s,6H); 4.99(t,1H);5.30(dd,1H); 6.56(s,2H); 7.72(m,2H); 7.85(m,2H). 108: 1.95(m,3H);2.00(m,2H); 2.20(m,1H); 3.51(m,1H); 3.83(s,3H); 3.85(m,2H); 3.88(s,6H);3.92(m,1H); 4.90(m,1H); 5.16(dd,1H); 6.60(s,2H); 7.72(m,2H); 7.84(m,2H).

In order to determine the stereochemistry of this molecule, an NOEdifference experiment was carried out.

Trans isomer (107): In this experiment the triplet at 4.99 ppm wasirradiated with a very low rf decoupling pulse and the data work-up wasdone so as to only measure the presence of an increase in signal. Thiswould represent a positive NOE effect and would indicate the closespacial relationship of these protons. In this experiment an NOE wasfound for the multiplet at 2.25-2.36 ppm which is a furan ring proton.Another NOE was also seen for the aromatic protons, indicating that thistriplet represents the benzylic proton. There was not an NOE observedfor the double doublet at 5.30 ppm indicating this was the trans isomer.

Cis isomer (108): In order to determine the stereochemistry of thismolecule an NOE difference experiment was carried out. In thisexperiment the multiplet at 4.88-4.93 ppm was irradiated with a very lowrf decoupling pulse and the data work-up was done so as to only measurethe presence of an increase in signal. This would represent a positiveNOE effect: and would indicate the close spacial relationship of theseprotons. In this experiment an NOE was found for the doublet at 5.16 ppmwhich is the other methine furan proton. Another NOE was also seen forthe aromatic protons indicating this triplet represents the benzylicproton. There was also an NOE observed for the multiplet at 1.93-2.20ppm for the other furan methylene protons.

(j) Preparation of 2-(4-Fluorophenyl)-5-(3-phthalimidyl propoxy)tetrahydrofuran (compounds 124, 125)

These compounds were prepared from 123 using a procedure similar to thatset forth in Example 1(i), replacing compound 105 with compound 123. ¹ HNMR (CDCl₃): 124 (trans): 1.65(m,1H); 1.80(m,1H); 2.00(m,2H);2.12(m,1H); 2.31(m,1H); 3.48(m,1H); 3.82(m,3H); 5.02(t,1H); 5.28(dd,1H);7.00(t,2H); 7.29(m,2H); 7.71(m,2H); 7.85(m,2H). 125 (cis): 1.90(m,2H);1.99(m,4H); 2.19(m,1H); 3.48(m,1H); 3.82(m,2H); 3.88(m,1H); 4.94(m,1H);5.15(dd,1H); 7.00(t,2H); 7.30(m,2H); 7.71(m,2H); 7.84(m,2H).

(k) Preparation of 3-phthalimidylpropanol (compound 106)

3-Bromopropanol (4.0 g, 28.78 mmol), potassium phthalimide (8.0 g, 43.17mmol) and potassium carbonate (4.0 g, 28.78 mmol) were added to 20 mLDMF. The reaction mixture was stirred at 70° C. for 4 hours, quenchedwith water and extracted with ethyl acetate. The organic layer waswashed with water, saturated NaCl solution and evaporated in vacuo to asolid which was crystallized in ethyl acetate (3.5 g, 67%).

(l) Preparation of trans and cis2-(3,4,5-trimethoxyphenyl)-5-(3-aminopropoxy)tetrahydrofuran (compounds109, 110)

Compound 107 (455 mg, 1.03 mmol) and hydrazine monohydrate (165.3 mg,5.16 mmol) were added to 2 mL ethanol. The reaction mixture was refluxedfor 2 hours, quenched with water and extracted with dichloromethane. Theorganic layer was washed with water and saturated NaCl solution, driedover MgSO₄, filtered and evaporated in vacuo to provide the transproduct 109 (225 mg, 70%). ¹ H NMR (CDCl₃): 1.75(m,2H); 1.78(m,1H);1.96(m,1H); 2.20(m,1H); 2.40(m,1H); 2.82(t,2H); 3.55(m,1H); 3.81(m,1H);3.83(s,3H); 3.87(s,6H); 5.00(t,1H); 5.34(dd,1H); 6.56(s,2H).

The cis isomer 110 was prepared from 108 using a procedure similar tothat described for 109. ¹ H NMR (CDCl₃): 1.76(m,2H); 2.08(m,3H);2.27(m,1H); 2.82(t,2H); 3.55(m,1H); 3.84(s,3H); 3.88(s,6H); 3.92(m,1H);4.95(m,1H); 5.20(m,1H); 6.64(s,2H).

(m) Preparation of 2-(4-fluorophenyl)-5-(3-aminopropoxy) tetrahydrofuran(compounds 126, 127)

These compounds were prepared from 124 and 125 using a procedure similarto that set forth in Example 1(l), replacing compounds 107 and 108 withcompounds 124 and 125. ¹ H NMR (CDCl₃): 124 (trans): 1.75(m,3H);1.96(m,1H); 2.20(m,1H); 2.40(m,1H); 2.82(t,2H); 3.54(m,1H); 3.83(m,1H);5.05(t,1H); 5.32(dd,1H); 7.01(t,2H); 7.30(m,2H). 125 (cis): 1.74(m,2H);1.97(m,1H); 2.05(m,2H); 2.25(m,1H); 2.77(t,2H); 3.47(m,1H); 3.85(m,1H);4.95(m,1H); 5.15(dd,1H); 7.00(t,2H); 7.34(m,2H).

(n) Preparation of trans and cis 2-(3,4,5-trimethoxyphenyl)-5-3-(N'-methyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran (compounds 1, 3)

Compound 109 (60 mg, 0.19 mmol) and triphosgene (23 mg, 0.078 mmol) weredissolved in 3 mL dichloromethane. Triethylamine (29.3, 0.29 mmol) wasadded to this solution. The reaction mixture was refluxed for 2 hoursand then cooled with ice bath. Triethylamine (34.0 mg, 0.34 mmol) andmethylhydroxyamine hydrochloride (32.2 mg, 0.39 mmol) were added to thecold solution. The reaction was stirred at room temperature for 16hours, quenched with water and extracted with dichloromethane. Theorganic layer was washed with saturated NaCl solution and evaporated invacuo to an oil which was purified by preparative TLC (silica, ethylacetate) to provide the trans product 1 (51 mg, 69%). ¹ H NMR (CDCl₃):1.82(m,3H); 1.95(m,1H); 2.22(m,1H); 2.40(m,1H); 3.15(s,3H); 3.40(m,2H);3.58(m,1H); 3.84(s,3H); 3.85(m,1H); 3.88(s,6H); 5.00(t,1H); 5.33(m,1H);6.32(m,1H); 6.56(s,2H); 7.37(s,1H).

The cis isomer 3 was prepared from 110 using a procedure similar to thatdescribed for 1. ¹ H NMR (CDCl₃): 1.83(m,2H); 2.07(m,3H); 2.28(m,1H);3.13(s,3H); 3.35(m,2H); 3.55(m,1H); 3.84(s,3H); 3.87(s,6H); 3.88(m,1H);4.97(m,1H); 5.20(m,1H); 6.22(m,1H); 6.63(s,2H); 7.37(s,1H).

(o) Preparation of 2-(4-fluorophenyl)-5-3-(N'-methyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran (compounds 9, 11)

These compounds were prepared from 126 and 127 using a procedure similarto that set forth in Example 1(n) replacing compounds 109 and 110 withcompounds 126 and 127. ¹ H NMR (CDCl₃): 9 (trans): 1.70(m,1H);1.78(m,2H); 1.96(m,1H); 2.19(m,1H); 2.40(m,1H); 3.10(s,3H); 3.31(m,2H);3.51(m,1H); 3.83(m,1H); 5.05(t,1H); 5.30(dd,1H); 6.38(t,1H); 7.01(t,2H);7.28(m,2H). 11 (cis): 1.80(m,2H); 2.05(m,3H); 2.24(m,1H); 3.06(s,3H);3.30(m,2H); 3.48(m,1H); 3.86(m,1H); 4.98(m,1); 5.16(dd,1H); 6.30(t,1H);7.02(t,2H); 7.31(m,2H); 8.08(bs,1H)

(p) Preparation of trans and cis 2-(3,4,5-trimethoxyphenyl)-53-(N'-n-butyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran (compounds 2,4)

Compound 109 (60 mg, 0.19 mmol) and triphosgene (23 mg, 0.078 mmol) weredissolved in 3 mL dichloromethane. Triethylamine (29.3, 0.29 mmol) wasadded to this solution. The reaction mixture was refluxed for 2 hoursand then cooled with ice bath. Butylhydroxyamine (51.4 mg, 0.29 mmol)was added to the cold solution. The reaction mixture was stirred at roomtemperature for 16 hours, quenched with water and extracted withdichloromethane. The organic layer was washed with saturated NaClsolution and evaporated in vacuo to an oil. The trans product 2 wasseparated by preparative TLC (silica, ethyl acetate) (46.9 mg, 57%). ¹ HNMR (CDCl₃): 0.93(t,3H); 1.35(m,2H); 1.58(m,2H); 1.81(m,3H); 1.96(m,1H);2.21(m,1H); 2.40(m,1H); 3.38(m,2H); 3.50(m,2H); 3.57(m,1H); 3.83(s,3H);3.85(m,1H); 3.88(s,6H); 5.00(t,1H); 5.32(m,1H); 6.32(m,1H); 6.56(s,2H).

The cis isomer 4 was prepared from 110 using a procedure similar to thatdescribed for 2. ¹ H NMR (CDCl₃): 0.92(t,3H); 1.32(m,2H); 1.58(m,2H);1.81(m,2H); 2.08(m,3H); 2.28(m,1H); 3.35(m,2H); 3.47(m,2H); 3.54(m,1H);3.84(s,3H); 3.87(s,6H); 3.88(M,1H); 4.97(m,1H); 5.20(m,1H); 6.22(m,1H);6.63(s,2H).

(q) Preparation of 2-(4-fluorophenyl)-53-(N'-n-butyl-N'-hydroxyureidyl)propoxy!tetrahydrofuran (compounds10,12)

These compounds were prepared from 126 and 127 using a procedure similarto that set forth in Example 1(p) replacing compounds 109 and 110 withcompounds 126 and 127. ¹ H NMR (CDCl₃): 10 (trans): 0.90(t,3H);1.30(m,2H); 1.55(m,2H); 1.70(m,1H); 1.78(m,2H); 1.96(m,1H); 2.19(m,1H);2.40(m,1H); 3.31(m,2H); 3.44(m,2H); 3.52(m,1H); 3.82(m,1H); 5.05(t,1H);5.30(dd,1H); 6.32(t,1H); 7.00(t,2H); 7.28(m,2H); 7.55(bs,1H). 12 (cis):0.90(t,3H); 1.30(m,2H); 1.52(m,2H); 1.80(m,2H); 2.04(m,3H); 2.24(m,1H);3.30(m,2H); 3.40(m,2H); 3.48(m,1H); 3.85(m,1H); 4.98(t,1H); 5.16(dd,1H);6.27(t,1H); 7.03(t,2H); 7.32(m,2H); 7.53(bs,1H).

EXAMPLE 2 Preparation of 2-(3,4-Dimethoxyphenyl)-5-3-N'-substituted-N'-hydroxyureidyl propoxy!tetrahydrofuran (5-8)

(a) Preparation of 4-(3',4'-dimethoxyphenyl)-4-oxobutyronitrile (111).

A single portion of neat acrylonitrile (3.2 ml, 0.048 mol) andtriethylamine (5 ml, 0.11 mol) was added to a stirred mixture of3,4-dimethoxybenzaldehyde (7.8 g, 0.047 mol) and3-benzyl-5-(2-hydroxyethyl)-4-methylthiazolium chloride (5.3 g, 0.02mol) in dry dimethylformamide (25 ml) under argon. The mixture was leftovernight at room temperature. The reaction was diluted with water andextracted with ethyl acetate (3×100 ml). The organic extract was washedwith water (3×100 ml), brine (3×100 ml) and the solvent was removedunder reduced pressure to give an amber oil. Analysis by TLC (silicagel; ethyl acetate:hexanes, 1:1) revealed a mixture of three spots at Rf0.80 (starting aldehyde), 0.50 (Compound 1) and 0.30 (unknownby-product). The sample was purified by column (flash) chromatography onsilica gel 60 (230-400 mesh) and eluted with ethyl acetate:hexanes (1:1)to give the desired compound (2.26 g, 22%) as a yellow solid. ¹ H NMR(CDCl₃) 2.78 (t, 2H, J=8 Hz), 3.33 (t, 2H, J=8 Hz), 3.96 (s, 3H), 3.98(s, 3H), 6.90(d, 1H, J=8.5 Hz), 7.52 (d, J=2 Hz, 2H), 7.58 (dd, J=2 and8 Hz, 2H).

(b) Preparation of 4-(3',4'-dimethoxyphenyl)-4-oxobutyric acid (112).

A stirred solution of 4-(3',4'-dimethoxyphenyl)-4-oxobutyronitrile (111)(2.26 g, 0.01 mol) in acetic acid (15 ml) and hydrochloric acid (12N, 40ml) was heated at reflux for 1.5 hours and cooled to room temperature.The solvent was removed under reduced pressure to give a brown solid.Recrystallization from water gave 112 as light tan crystals (1.57 g,66%). ¹ H NMR (CDCl₃) 2.80 (t, J=7.5 Hz, 2H), 3.30 (t, J=7.5 Hz, 2H),3.94 (s, 3H), 3.96 (s, 3H), 6.89 (d, 1H, J=9 Hz), 7.55 (d, 1H, J=1 Hz)and 7.64 (dd, 1H, 1 and 9 Hz).

(c) Preparation of 4-(3',4'-dimethoxyphenyl)butyrolactone (113).

A solution of sodium borohydride (0.89 g, 0.023 mol) in water (4 ml) wasadded dropwise (ca. 5 min) to a stirred solution of 112 (2.8 g, 0.012mol) in dry, freshly distilled tetrahydrofuran (40 ml) and methanol (20ml) under argon. The reaction was left overnight at room temperature.Analysis by TLC (silica gel; ethyl acetate:methanol:acetic acid,9.5:0.5:few drops) indicated the presence of starting material. Anadditional charge of sodium borohydride (0.5 g, 0.013 mol) in water (2ml) was added dropwise and the reaction left at room temperature forthree hours. Analysis by TLC (same system as above) indicated theabsence of starting material. The reaction was quenched withhydrochloric acid (6N, 25 ml) and left at room temperature for 15minutes. The mixture was extracted with ethyl acetate (3×75 ml). Theorganic extract was washed with water (3×75 ml), brine (3×75 ml) and thesolvent removed under reduced pressure to give a tan solid (2.0 g, 75%).¹ H NMR (CDCl₃) 2.18-2.25 (m, 1H), 2.59-2.70 (m, 3H), 3.89 (s, 3H), 3.90(s, 3H), 5.44-5.49 (m, 1H) and 6.82-6.87 (m, 3H).

(d) Preparation of 4-(3',4'-dimethoxyphenyl)butyrolactol (114).

A solution of diisobutylaluminum hydride (1.5M, 9 ml, 13.5 mmol) wasadded in a dropwise manner (ca. 30 min.) to 113 (2.0 g, 9 mmol) in drytoluene (40 ml) under argon which was cooled by a dry ice-acetone bath.The reaction was stirred at -78° C. for one hour. Analysis by TLC(silica gel; ethyl acetate:hexanes, 1:1) revealed the absence ofstarting material and the presence of a new spot at Rf 0.38. Thereaction was quenched with methanol (20 ml) and slowly warmed to 0° C. Asaturated solution of sodium potassium tartrate (50 ml) was added andstirred at 0° C. for 45 minutes. The mixture was extracted with ethylacetate (3×100 ml) and the organic extract washed with water (3×75 ml)and brine (3×75 ml). Removal of the solvent under reduced pressure gavea dark amber oil (1.7 g, 84%). ¹ H NMR (CDCl₃) (mixture of cis and transisomers) 1.71-2.49 (m, 8H), 2.91 (br s, 1H), 3.09 (br s, 1H), 3.89 (s,6H), 3.90(s, 6H), 4.97 (m, 1H), 5.19 (t, J=7Hz, 1H), 5.62 (m, 1H), 5.77(m, 1H) and 6.82-7.28 (m, 6H).

(e) Preparation of N-(3-hydroxypropyl)phthalimide (106).

A mixture of 3-bromopropanol (4 g, 0.029 mol), potassium phthalate (8 g,0.043 mol) and potassium carbonate (4 g, 0.029 mol) in dry DMF (50 ml)was stirred and heated at 70° C. for four hours. The mixture was dilutedwith water (100 ml) and extracted with ethyl acetate (3×75 ml). Theorganic extract was washed with water (3×100 ml) and dried (Na₂ SO4).Removal of the solvent under reduced pressure left a white solid whichwas extracted with benzene. The benzene extract was evaporated to awhite solid and recrystallized from ethyl acetate-hexanes to give whitecrystals (1.27 g, 24%).

(f) Preparation of trans and cis 2-(3',4'-dimethoxyphenyl)-5-3-(N-phthaloyl)!propoxytetrahydrofuran (115 and 116).

Triflic anhydride (0.68 ml, 4.8 mmol) was added in a single portion to astirred solution of 114 (0.72 g, 3.2 mmol) in dry dichloromethane (20ml) and triethylamine (0.68 ml, 4.9 mmol) under argon which was cooledusing an ice bath. The reaction was stirred at 0° C. for 30 minutes.N-(3-hydroxypropyl)phthalimide (106) (1.27 g, 7 mmol) was added to thereaction mixture and the solution was allowed to warm to roomtemperature and left at this temperature for two hours. The solution wasquenched with aqueous sodium bicarbonate solution (saturated, 25 ml) andextracted with ethyl acetate (3×50 ml), brine (3×50 ml) and dried(sodium sulfate). Removal of the solvent under reduced pressure left anamber oil (2.02 g). Analysis of the oil by TLC (silica gel; ethylacetate:hexanes, 1:1) revealed the presence of four spots at Rf 0.80,0.60, 0.50 and 0.35. The spots at Rf 0.60 and 0.50 were in a 2:1 ratio.The sample was purified by column chromatography (flash) on silica gel(230-400 mesh) and eluted with ethyl acetate:hexanes (3:7) to give firstthe substance at Rf 0.60 as a clear and colorless oil (0.40 g, 30%),identified as trans 2-(3',4'-dimethoxyphenyl)-5-3-(N-phthaloyl)!-propoxytetrahydrofuran (115) (0.40 g, 30%). ¹ H NMR(CDCl₃) 1.34-1.94 (m, 2H), 1.96-2.05 (m, 2H), 2.09-2.20 (m, 1H),2.25-2.36 (m, 1H), 3.46-3.53 (m, 1H), 3.84 (t, 9 Hz, 2H), there is alsoa hidden 1 proton multiplet here, 3.88 (s, 3H), 3.91 (s, 3H), 5.01 (t,7.3Hz, 1H), 5.30 (dd, J=2 and 5 Hz, 1 Hz), 6.82-6.90 (m, 3H), 7.71-7.74(m, 2H) and 7.84-7.88 (m, 2H).

In order to determine the stereochemistry of this molecule and NOEdifference experiment was carried out. In this experiment the triplet at5.01 ppm was irradiated with a very low rf decoupling pulse and the datawork-up was done so as to only measure the presence of an increase insignal. This would represent a positive NOE effect and would indicatethe close spatial relationship of these protons. In this experiment anNOE was found for the multiplet at 2.25-2.36 ppm which is a furan ringproton. Another NOE was also seen for the aromatic protons indicatingthis triplet presents the benzylic proton. There was not an NOE observedfor the double doublet at 5.30 ppm indicating this was the trans isomer.

Continued elution with the same solvent system gave the spot at Rf 0.50as a colorless oil (0.21 g, 15%), identified as cis2-(3',4'-dimethoxyphenyl)-5- 3-(N-phthaloyl)!propoxy-tetrahydrofuran(116). ¹ H NMR (CDCl₃) 1.92-2.12 (m, 6H), 3.44-3.52 (m, 1H), 3.86 (s,3H), 3.88 (s, 3H), 3.76-3.93 (m, 3H), 4.89-4.94 (m, 1H), 5.35 (d, J=4Hz), 6.89 (d, J=8 Hz), 6.87 (dd, J=2 and 8 Hz), 6.92 (d, J=2 Hz),7.69-7.72 (m, 2H) and 7.82-7.85 (m, 2H).

In order to determine the stereochemistry of this molecule an NOEdifference experiment was carried out. In this experiment the multipletat 4.89-4.94 ppm was irradiated with a very low rf decoupling pulse andthe data work-up was done so as to only measure the presence of anincrease in signal. This would represent a positive NOE effect and wouldindicate the close spatial relationship of these protons. In thisexperiment an NOE was found for the doublet at 5.35 ppm which is theother methine furan proton. This indicates that this molecule is the cisisomer. Another NOE was also seen for the aromatic protons indicatingthis triplet presents the benzylic proton. There was also an NOE presentfor the multiplet at 1.92-2.12 ppm which contains the other furanmethylene protons.

The chromatography also yielded a mixture of 115 and 116 (0.342 g, 26%).

(g) Preparation of trans2-(3',4'-dimethoxyphenyl)-5-(3-aminopropoxy)tetrahydrofuran (117).

Neat hydrazine hydrate (150 μl, 3.2 mmol) was added to a stirredsolution of 115 (253 mg, 0.62 mmol) in absolute ethanol (1.5 ml). Thesolution was heated at reflux for 5 minutes whereupon a white solidprecipitated out of solution. The mixture was heated at reflux for twohours. Analysis by TLC (silica gel; ethyl acetate:hexanes, 1:1) revealedthe absence of starting material and the presence of a spot at theorigin. The reaction was quenched with water (10 ml) and extracted withdichloromethane (5×10 ml). The organic phase was washed with water (2×10ml), brine (2×10 ml) and dried (sodium sulfate). Removal of the solventunder reduced pressure left a colorless oil (150 mg, 86%). ¹ H NMR(CDCl₃) 1.25 (br s, 2H), 1.68-1.78 (m, 3H), 1.81-1.98 (m, 1H), 2.14-2.2(m, 1H), 2.3-2.36 (m, 1H), 2.80 (t, J=6.5 Hz, 2H), 3.47-3.55 (m, 1H),3.78-3.87 (m, partially hidden, 1H), 3.86 (s, 3H), 3.88 (s, 3H), 4.99(t, J=7 Hz, 1H), 5.31 (dd, J=2 and 6 Hz, 1H), 6.80-6.88 (m, 3H).

(h) Preparation of cis2-(3',4'-dimethoxyphenyl)-5-(3-aminopropoxy)tetrahydrofuran (118).

Neat hydrazine hydrate (125 μl, 2.57 mmol) was added to a stirredsolution of 116 (210 mg, 0.51 mmol) in absolute ethanol (3.0 ml). Thesolution was heated at ref lux for 5 minutes whereupon a white solidprecipitated out of solution. The mixture was heated at reflux for twohours. Analysis by TLC (silica gel; ethyl acetate:hexanes, 1:1) revealedthe absence of starting material and the presence of a spot at theorigin. The reaction was quenched with water (10 ml) and extracted withdichloromethane (5×10 ml). The organic phase was washed with water (2×10ml), brine (1×10 ml) and dried (sodium sulfate). Removal of the solventunder reduced pressure left a stiff oil (105 mg, 73%). ¹ H NMR (CDCl₃)1.45 (br s, 2H), 1.73-1.78 (m, 2H), 2.01-2.12 (m, 3H), 2.19-2.29 (m,1H), 2.81 (t, J=7 Hz, 2H), 3.48-3.53 (m, 1H), 3.85-3.93 (m, partiallyhidden, 1H), 3.88 (s, 3H), 3.90 (s, 3H), 4.96-5.01 (m, 1H), 5.17 (dd,J=3 and 6 Hz, 1H), 6.83 (d, J=8 Hz, 1H), 6.89 (dd, J=2 and 8 Hz, 1H) and6.96 (d, J=2 Hz, 1H).

(i) Preparation of trans 2-(3',4'-dimethoxyphenyl)-5-3-(N-butyl-N-hydroxyureidyl)propoxy!tetrahydrofuran (5).

Triethylamine (32 μl, 0.22 mmol) and then triphosgene (19 mg, 0.06 mmol)were added to a stirred solution of 117 (53 mg, 0.19 mmol) in drydichloromethane (3 ml) under argon. The solution was heated at refluxfor 30 minutes and cooled to room temperature. Solidn-butylhydroxylamine (34 mg, 0.38 mmol) was added in one portion to thesolution which was left overnight at room temperature. The reaction wasquenched with water (10 ml) and extracted with dichloromethane (3×10ml). The combined organic phase was washed with aqueous sodiumbicarbonate solution (saturated, 3×10 ml) and dried (sodium sulfate).Analysis by TLC (silica gel, ethyl acetate) revealed a complex mixtureRf 0.90, 0.50, 0.25 and 0.00. The sample was purified by column (flash)chromatography on silica gel 60 (230-400 mesh) and eluted with ethylacetate to give the spot at Rf 0.50 as an opaque oil (8 mg, 11%). ¹ HNMR (CDCl₃) 0.92 (t, J=7 Hz, 3H), 1.27-1.39 (m, 2H), 1.51-1.61 (m, 2H),1.71-1.86 (m, 3H), 1.88-2.15 (m, 1H), 2.17-2.29 (m, 1H), 2.32-2.42 (m,1H), 3.28-3.58 (m, 4H), 3.81-3.94 (m, partially hidden, 2H), 3.87 (s,3H), 3.90 (s, 3H), 5.49-5.05 (m, 1H), 5.31-5.38 (m, 1H), 6.28-6.34 (m,1H) and 6.81-6.86 (m, 3H). IR (film) 3407, 3193, 2933, 1640, 1516, 1263,1029 cm⁻¹

(j) Preparation of trans 2-(3',4'-dimethoxyphenyl)-5-3-(N-methyl-N-hydroxyureidyl)propoxy!tetrahydrofuran (6).

Triphosgene (12 mg, 0.04 mmol), followed immediately by triethylamine(17 μl, 0.12 mmol) was added to a stirred solution of 117 (32 mg, 0.011mmol) in dry dichloroinethane (3 ml) under argon. The solution washeated at reflux for 2 hours, cooled to room temperature and placed inan ice bath. Neat triethylamine (32 μl, 0.23 mmol) followed bymethylhydroxylamine hydrochloride salt (19 mg, 0.23 mmol) was added tothe reaction mixture. The reaction was left overnight at roomtemperature. It was then quenched with water (10 ml) and extracted withdichloromethane (3×10 ml). The organic extract was washed with water(3×10 ml), brine (3×10 ml) and the solvent was removed under reducedpressure to give an amber oil. Analysis by TLC (silica gel, ethylacetate) revealed only one new spot at Rf 0.30. The sample was purifiedby column (flash) chromatography on silica gel 60 (230-400 mesh) andeluted with ethyl acetate to give the desired compound as an amber oil(12 mg, 30%). ¹ H NMR (CDCl₃) 1.73-1.84 (m, 2H), 1.90-2.01 (m, 1H),2.03-2.13 (m, 1H), 2.18-2.29 (m, 1H), 2.32-2.43 (m, 1H), 3.13 (s, 3H),3.30-3.44 (m, 2H), 3.49-3.59 (m, 1H), 3.82-3.92 (m, partially hidden,3H), 3.88 (s, 3H), 3.91 (m, 3H), 4.96-5.04 (m, 1H), 5.34 (dd, J=2 and 5Hz, 1H), 6.34 (br t, 5 Hz, 1H) and 6.82-6.68 (m, 3H). IR (film) 3407,3229, 2935, 1636, 1516, 1263 and 1029 cm⁻¹.

(k) Preparation of cis 2-(3',4'-dimethoxyphenyl)-5-3-(N-butyl-N-hydroxyureidyl)propoxy!-tetrahydrofuran (7).

Triphosgene (18 mg, 0.06 mmol), followed immediately by triethylamine(80 μl, 0.57 mmol) were added to a stirred solution of 118 (50 mg, 0.18mmol) in dry dichloromethane (3 ml) under argon. The solution was heatedat reflux for 2 hours, cooled to room temperature and placed in an icebath. Neat triethylamine (50 μl, 0.35 mmol) was added, followed by solidn-butylhydroxylamine (32 mg, 0.36 mmol). The reaction was left overnightat room temperature. It was then quenched with water (10 ml) andextracted with dichloromethane (3×10 ml). The organic extract was washedwith water (3×10 ml), brine (3×10 ml), and the solvent was removed underreduced pressure to give an amber oil. Analysis by TLC (silica gel,ethyl acetate) revealed two new spots in approximately equal amounts atRf 0.85 and 0.45. The sample was purified by column (flash)chromatography on silica gel 60 (230-400 mesh) and eluted with ethylacetate to give first the spot at Rf 0.85 as an amber oil (26 mg).Continued elution with the same solvent system then gave the titlecompound as an amber oil (25 mg, 35%). ¹ H NMR (CDCl₃) 1.1 (t, J=7 Hz,3H), 1.25-1.37 (m, 2H), 1.49-1.59 (m, 2H), 1.76-1.84 (m, 2H), 1.99-2.1(m, 3H), 2.19-2.26 (m, 1H), 3.26-3.54 (m, 5H), 3.84-3.92 (m, partiallyhidden, 1H), 3.87 (s, 3H), 3.88 (s, 3H), 4.94-5.02 (m, 1H), 5.17 (d, J=4Hz, 1H), 6.24 (t, J=4 Hz, 1H), 6.52 (br s, 1H), 6.83 (d, J=8 Hz, 1H) and6.89-95 (m, 2H). IR (film) 2913, 1640, 1570, 1463, 1262, 1139 and 1031cm⁻¹.

(l) Preparation of cis 2-(3',4'-dimethoxyphenyl)-5-3-(N-methyl-N-hydroxyureidyl)propoxy!tetrahydrofuran (8).

Triphosgene (20 mg, 0.07 mmol), followed immediately by triethylamine(80 μl, 0.57 mmol)were added to a stirred solution of 118 (56 mg, 0.2mmol) in dry dichloromethane (3 ml) under argon. The solution was heatedat reflux for 2 hours, cooled to room temperature and placed in an icebath. Neat triethylamine (80 μl, 0.57 mmol) was added followed by solidmethyl hydroxylamine hydrochloride salt (32 mg, 0.39 mmol). The reactionwas left overnight at room temperature. It was then quenched with water(10 ml) and extracted with dichloromethane (3×10 ml). The organicextract was washed with water (3×10 ml), brine (3×10 ml), and thesolvent was removed under reduced pressure to give an amber oil.Analysis by TLC (silica gel, ethyl acetate) revealed one spot at rf 0.30and some material at the origin. The sample was purified by column(flash) chromatography on silica gel 60 (230-400 mesh) and eluted withethyl acetate to give the title compound as an amber oil (30 mg, 42%). ¹H NMR (CDCl₃) 1.76 (m, 2H), 1.98-2.10 (m, 3H), 2.18-2.26 (m, 1H), 3.07(s, 3H), 3.25-3.37 (m, 2H), 3.46-3.54 (m, 1H), 3.85-3.90 (m, partiallyhidden, 1H), 3.87 (s, 3H), 3.88 (s, 3H), 4.93-5.00 (m, 1H), 5.16 (d, J=4Hz, 1H), 6.27 (t, J=5 Hz, 1H), 6.83 (d, J=8 Hz, 1H) and 6.88-6.93 (m,2H). IR (neat) 2933, 1643, 1518, 1261 and 1029 cm⁻¹.

EXAMPLE 3 Preparation of 2-(2,4,5-trimethoxyphenyl)-5-(3-hydroxyureidylpropoxy)tetrahydrofuran (13) and2-(4-fluorophenyl)5-(3-hydroxyureidylpropoxy)tetrahydrofuran (14, 15)

(a) Preparation of 2-(3,4,5-trimethoxyphenyl)-5-(3-bromopropoxy)tetrahydrofuran (compound 128)

Compound 105 (1.0 g, 3.94 mmol) was dissolved in 4 mL dichloromethane.Triethylamine (597 mg, 5.90 mmol) was added to this solution. Thereaction mixture was cooled with an ice bath and trifluoroaceticanhydride (1.24 g, 5.90 mmol) was added dropwise. The reaction mixturewas stirred at 0° C. for 30 minutes and then 3-bromopropanol (1.84 g,13.27 mmol) was added. The reaction mixture was warmed to roomtemperature and stirred at room temperature for 2 hours. The reactionwas quenched with saturated aqueous NaHCO₃ solution and extracted withethyl acetate. The organic layer was washed with water and saturatedNaCl solution, dried over MgSO₄, filtered and evaporated in vacuo to anoil which was purified by column chromatography (silica, 4:1hexane/ethyl acetate) (128: 430 mg and its cis isomer 250 mg; totalyield 46%). ¹ H NMR (CDCl₃): 128 (trans): 1.77(m,1H); 1.98(m,1H);2.15(m,2H); 2.20(m,1H); 2.40(m,1H); 3.53(t,2H); 3.60(m,1H); 3.83(s,3H);3.87(m,1H); 3.89(s,6H); 5.01(t,1H); 5.35(dd,1H); 6.57(s,2H).

(b) Preparation of 2-(4-fluorophenyl)-5-(3-bromopropoxy) tetrahydrofuran(compounds 129, 130)

These compounds were prepared from 123 using a procedure similar to thatset forth in Example 3(a), replacing compound 105 with compound 123. ¹ HNMR (CDCl₃): 129 (trans): 1.72(m,1H); 1.98(m,1H); 2.14(m,2H);2.20(m,1H); 2.40(m,1H); 3.53(t,2H); 3.60(m,1H); 3.89(m,1H); 5.06(t,1H);5.34(m,1H); 7.02(t,2H); 7.30(m,2H). 130 (cis): 1.98(m,1H); 2.07(m,2H);2.14(m,2H); 2.26(m,1H); 3.52(t,2H); 3.58(m,1H); 3.93(m,1H); 5.00(m,1H);5.20(dd,1H); 7.03(t,2H); 7.35(m,2H).

(c) Preparation of2-(3,4,5-trimethoxyphenyl)-5-(3-O-benzylhydroxylaminopropoxy)tetrahydrofuran(compounds 131)

Compound 128 (260 mg, 0.69 mmol) was dissolved in 2 mL1,3-dimethyl-3,4,5,6-tetrahydro-2-(1H)-pyrimidinone (DMPU). Sodiumcarbonate (220.4 mg, 2.08 mmol) and benzylhydroxylamine hydrochloride(166 mg, 1.04 mmol) were added to this solution. The reaction wasstirred at 80° C. for 16 hours, quenched with water and extracted withethyl acetate. The organic layer was washed with water and saturatedsodium chloride solution, dried over MgSO₄, filtered and evaporated toan oil which was purified by column (flash) chromatography using ethylacetate as a solvent (114 mg, 40%). ¹ H NMR (CDCl₃): 1.72(m,1H);1.82(m,2H); 1.92(m,1H); 2.18(m,1H); 2.36(m,1H); 3.06(t,2H); 3.52(m,1H);3.81(m,1H); 3.83(s,3H); 3.87(s,6H); 4.71(s,2H); 4.98(t,1H); 5.30(dd,1H);6.55(s,2H); 7.35(m,5H).

(d) Preparation of2-(4-fluorophenyl)-5-(3-O-benzylhydroxylaminopropoxy)tetrahydrofuran(compounds 132,133)

These compounds were prepared from compounds 129 and 130 using aprocedure similar to that set forth in Example 3(c), replacing compound128 with compounds 129 and 130. ¹ H NMR (CDCl₃): 132 (trans):1.70(m,1H); 1.83(m,2H); 1.94(m,1H); 2.17(m,1H); 2.38(m,1H); 3.07(t,2H);3.52(m,1H); 3.82(m,2H); 4.71(s,2H); 5.02(t,1H); 5.30(ss,1H); 7.02(t,2H);7.30(m,2H); 7.36(m,5H). 133 (cis): 1.85(m,2H); 1.96(m,1H); 2.05(m,2H);2.26(m,1H); 3.05(t,2H); 3.50(m,1H); 3.88(m,2H); 4.70(s,2H); 4.99(m,1H);5.17(dd,1H); 5.50(bs,1H); 7.00(t,2H); 7.35(m,7H)

(e) Preparation of2-(3,4,5-trimethoxyphenyl)-5-(3-O-benzylhydroxyureidylpropoxy)tetrahydrofuran(compounds 134)

Compound 131 (114 mg, 0.27 mmol) was dissolved in 3 mL dichloromethane.Trimethylsilyl isocyanate (47.6 mg, 0.41 mmol) was added to thissolution. The reaction was stirred at room temperature for 16 hours andthen refluxed for 4 hours. The reaction was quenched with saturatedammonium chloride solution, extracted with ethyl acetate and evaporatedto an oil. The product was isolated by preparative TLC using ethylacetate as solvent. ¹ H NMR (CDCl₃): 1.72(m,1H); 1.94(m,3H); 2.16(m,1H);2.38(m,1H); 3.50(m,1H); 3.62(m,2H); 3.80(m,1H); 3.82(s,3H); 3.84(s,6H);4.81(s,2H); 4.99(t,1H); 5.30(m,3H); 6.54(s,2H); 7.37(s,5H).

(f) Preparation of2-(4-fluorophenyl)-5-(3-O-benzylhydroxyureidylpropoxy)tetrahydrofuran(compounds 135, 136)

These compounds were prepared from 132 and 133 using a procedure similarto that set forth in Example 3(e), replacing compounds 131 withcompounds 132 and 133. ¹ H NMR (CDCl₃): 135 (trans): 1.70(m,1H);1.93(m,3H); 2.16(m,1H); 2.39(m,1H); 3.50(m,1H); 3.62(m,2H); 3.80(m,1H);4.82(s,2H); 5.04(t,1H); 5.30(dd,1H); 5.35(bs,2H); 7.00(t,2H);7.29(m,2H); 7.38(s,5H). 136 (cis): 1.98(m,4H); 2.08(m,1H); 2.25(m,1H);3.48(m,1H); 3.62(m,2H); 3.83(m,1H); 4.81(s,2H); 4.98(m,1H); 5.17(dd,1H);5.42(bs,1H); 7.00(t,2H); 7.33(m,2H); 7.38(s,5H).

(g) Preparation of2-(3,4,5-trimethoxyphenyl)-5-(3-hydroxyureidylpropoxy)tetrahydrofuran(compounds 13)

Compound 134 (90 mg, 0.19 mmol) was dissolved in 2 mL ethyl acetate andthen Pd/C (10%) (18 mg) was added. The reaction mixture was hydrogenatedat balloon pressure for 16 hours. The reaction was filtered and thefiltrate was concentrated. The product was isolated by preparative TLCusing ethyl acetate as solvent (68 mg). ¹ H NMR (CDCl₃): 1.75(m,1H);1.91(m,2H); 1.95(m,1H); 2.20(m,1H); 2.37(m,1H); 3.58(m,1H); 3.66(m,2H);3.81(s,3H); 3.85(m,1H); 3.87(m,6H); 5.00(t,1H); 5.35(dd,1H);5.41(bs,2H); 6.53(s,2H); 8.39(s,1H).

(h) Preparation of2-(4-fluorophenyl)-5-(3-hydroxyureidylpropoxy)tetrahydrofuran (compounds14, 15)

Compounds 14 and 15 were prepared from 135 and 136 using a proceduresimilar to that set forth in Example 3(g), replacing compound 134 withcompounds 135 and 136. ¹ H NMR (CDCl₃): 14 (trans): 1.72(m,1H);1.93(m,3H); 2.20(m,1H); 2.38(m,1H); 3.58(m,1H); 3.67(m,2H); 3.85(m,1H);5.05(t,1H); 5.33(dd,1H); 5.48(bs,2H); 7.00(t,2H); 7.28(m,2H);8.48(bs,1H). 15 (cis): 1.92(m,2H); 2.01(m,1H); 2.10(m,2H); 2.26(m,1H);3.53(m,1H); 3.64(m,2H); 3.87(m,1H); 4.98(m,1H); 5.20(dd,1H);5.43(bs,2H); 7.01(m,2H); 7.31(m,2H); 8.43(bs,1H).

II. Pharmaceutical Compositions

Humans, equines, canines, bovines and other animals, and in particular,mammals, suffering from inflammatory diseases, and in particular,disorders mediated by PAF or products of 5-lipoxygenase can be treatedby administering to the patient an effective amount of one or more ofthe above-identified compounds or a pharmaceutically acceptablederivative or salt thereof in a pharmaceutically acceptable carrier ordiluent to reduce formation of oxygen radicals. The active materials canbe administered by any appropriate route, for example, orally,parenterally, intravenously, intradermally, subcutaneously, ortopically, in liquid, cream, gel, or solid form, or by aerosol form.

As used herein, the term pharmaceutically acceptable salts or complexesrefers to salts or complexes that retain the desired biological activityof the above-identified compounds and exhibit minimal undesiredtoxicological effects. Non-limiting examples of such salts are (a) acidaddition salts formed with inorganic acids (for example, hydrochloricacid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid, andthe like), and salts formed with organic acids such as acetic acid,oxalic acid, tartaric acid, succinic acid, malic acid, ascorbic acid,benzoic acid, tannic acid, pamoic acid, alginic acid, polyglutamic acid,naphthalenesulfonic acid, naphthalenedisulfonic acid, andpolygalacturonic acid; (b) base addition salts formed with metal cationssuch as zinc, calcium, bismuth, barium, magnesium, aluminum, copper,cobalt, nickel, cadmium, sodium, potassium, and the like, or with acation formed from ammonia, N,N-dibenzylethylene-diamine, D-glucosamine,tetraethylammonium, or ethylenediamine; or (c) combinations of (a) and(b); e.g., a zinc tannate salt or the like. The compounds can also beadministered as pharmaceutically acceptable quaternary salts known bythose skilled in the art, which specifically include the quaternaryammonium salt of the formula --NR⁺ Z⁻, wherein R is alkyl or benzyl, andZ is a counterion, including chloride, bromide, iodide, -O-alkyl,toluenesulfonate, methylsulfonate, sulfonate, phosphate, or carboxylate(such as benzoate, succinate, acetate, glycolate, maleate, malate,citrate, tart:rate, ascorbate, benzoate, cinnamoate, mandeloate,benzyloate, and diphenylacetate.

The active compound is included in the pharmaceutically acceptablecarrier or diluent in an amount sufficient to deliver to a patient atherapeutically effective amount without causing serious toxic effectsin the patient treated. A preferred dose of the active compound for allof the above-mentioned conditions is in the range from about 10 ng/kg to300 mg/kg, preferably 0.1 to 100 mg/kg per day, more generally 0.5 toabout 25 mg per kilogram body weight of the recipient per day. Apreferred dosage for cardiovascular indications is in the range 10 ng/kgto 20 mg/kg. A typical topical dosage will range from 0.01-3% wt/wt in asuitable carrier. The effective dosage range of the pharmaceuticallyacceptable derivatives can be calculated based on the weight of theparent compound to be delivered. If the derivative exhibits activity initself, the effective dosage can be estimated as above using the weightof the derivative, or by other means known to those skilled in the art.

The compound is conveniently administered in any suitable unit dosageform, including but not limited to one containing 1 to 3000 mg,preferably 5 to 500 mg of active ingredient per unit dosage form. A oraldosage of 25-250 mg is usually convenient.

The active ingredient is preferably administered to achieve peak plasmaconcentrations of the active compound of about 0.00001-30 mM, preferablyabout 0.1-30 μM. This may be achieved, for example, by the intravenousinjection of a solution or formulation of the active ingredient,optionally in saline, or an aqueous medium or administered as a bolus ofthe active ingredient.

The concentration of active compound in the drug composition will dependon absorption, distribution, inactivation, and excretion rates of thedrug as well as other factors known to those of skill in the art. It isto be noted that dosage values will also vary with the severity of thecondition to be alleviated. It is to be further understood that for anyparticular subject, specific dosage regimens should be adjusted overtime according to the individual need and the professional judgment ofthe person administering or supervising the administration of thecompositions, and that the concentration ranges set forth herein areexemplary only and are not intended to limit the scope or practice ofthe claimed composition. The active ingredient may be administered atonce, or may be divided into a number of smaller doses to beadministered at varying intervals of time.

Oral compositions will generally include an inert diluent or an ediblecarrier. They may be enclosed in gelatin capsules or compressed intotablets. For the purpose of oral therapeutic administration, the activecompound can be incorporated with excipients and used in the form oftablets, troches, or capsules. Pharmaceutically compatible bindingagents, and/or adjuvant materials can be included as part of thecomposition.

The tablets, pills, capsules, troches and the like can contain any ofthe following ingredients, or compounds of a similar nature: a bindersuch as microcrystalline cellulose, gum tragacanth or gelatin; anexcipient such as starch or lactose, a dispersing agent such as alginicacid, Primogel, or corn starch; a lubricant such as magnesium stearateor Sterotes; a glidant such as colloidal silicon dioxide; a sweeteningagent such as sucrose or saccharin; or a flavoring agent such aspeppermint, methyl salicylate, or orange flavoring. When the dosage unitform is a capsule, it can contain, in addition to material of the abovetype, a liquid carrier such as a fatty oil. In addition, dosage unitforms can contain various other materials which modify the physical formof the dosage unit, for example, coatings of sugar, shellac, or entericagents.

The active compound or pharmaceutically acceptable salt or derivativethereof can be administered as a component of an elixir, suspension,syrup, wafer, chewing gum or the like. A syrup may contain, in additionto the active compounds, sucrose as a sweetening agent and certainpreservatives, dyes and colorings and flavors.

The active compound or pharmaceutically acceptable derivatives or saltsthereof can also be mixed with other active materials that do not impairthe desired action, or with materials that supplement the desiredaction, such as antibiotics, antifungals, othe Solunflammatories, orantiviral compounds.

Solutions or suspensions used for parenteral, intradermal, subcutaneous,or topical application can include the following components: a sterilediluent such as water for injection, saline solution, fixed oils,polyethylene glycols, glycerine, propylene glycol or other syntheticsolvents; antibacterial agents such as benzyl alcohol or methylparabens; antioxidants such as ascorbic acid or sodium bisulfite;chelating agents such as ethylenediaminetetraacetic acid; buffers suchas acetates, citrates or phosphates and agents for the adjustment oftonicity such as sodium chloride or dextrose. The parental preparationcan be enclosed in ampoules, disposable syringes or multiple dose vialsmade of glass or plastic.

If administered intravenously, preferred carriers are physiologicalsaline or phosphate buffered saline (PBS).

In one embodiment, the active compounds are prepared with carriers thatwill protect the compound against rapid elimination from the body, suchas a controlled release formulation, including implants andmicroencapsulated delivery systems. Biodegradable, biocompatiblepolymers can be used, such as ethylene vinyl acetate, polyanhydrides,polyglycolic acid, collagen, polyorthoesters, and polylactic acid.Methods for preparation of such formulations will be apparent to thoseskilled in the art. The materials can also be obtained commercially fromAlza Corporation (CA) and Scios Nova (Baltimore, Md.).

Liposomal suspensions may also be pharmaceutically acceptable carriers.These may be prepared according to methods known to those skilled in theart, for example, as described in U.S. Pat. No. 4,522,811 (which isincorporated herein by reference in its entirety). For example, liposomeformulations may be prepared by dissolving appropriate lipid(s) (such asstearoyl phosphatidyl ethanolamine, stearoyl phosphatidyl choline,arachadoyl phosphatidyl choline, and cholesterol) in an inorganicsolvent that is then evaporated, leaving behind a thin film of driedlipid on the surface of the container. An aqueous solution of the activecompound or its monophosphate, diphosphate, and/or triphosphatederivatives are then introduced into the container. The container isthen swirled by hand to free lipid material from the sides of thecontainer and to disperse lipid aggregates, thereby forming theliposomal suspension.

III. Biological Activity

A wide variety of biological assays have been used to evaluate theability of a compound to act as a PAF receptor antagonist, including theability of the compound to bind to PAF receptors, and the effect of thecompound on various PAF mediated pathways. Any of these known assays canbe used to evaluate the ability of the compounds disclosed herein to actas PAF receptor antagonists.

For example, PAF is known to induce hemoconcentration and increasedpermeability of microcirculation leading to a decrease in plasma volume.PAF mediated acute circulatory collapse can be used as the basis of anassay to evaluate the ability of a compound to act as a PAF antagonist,by analyzing the effect of the compound on PAF induced decreased plasmavolume in an animal model such as mouse.

Endotoxemia causes the release of chemical mediators includingeicosanoids, PAF, and tumor necrosis factor (TNF) that stimulate avariety of physiologic responses including fever, hypotension,leukocytosis, and disturbances in glucose and lipid metabolism.Endotoxemia can result in severe shock and death. Endotoxin-inducedmouse mortality is a useful animal model to evaluate the pharmacologicaleffect of compounds on endotoxic shock.

Two other common assays used to evaluate the ability of a compound toact as a PAF receptor antagonist are platelet aggregation in vitro andhypotension in rats (Shen, et al., "The Chemical and BiologicalProperties of PAF Agonists, Antagonists, and Biosynthetic Inhibitors",Platelet-Activating Factor and Related Lipid Mediators, F. Snyder, Ed.Plenum Press, New York, N.Y. 153 (1987)).

A wide variety of biological assays have also been used to evaluate theability of a compound to inhibit the enzyme 5-lipoxygenase. For example,a cytosol 5-lipoxygenase of rat basophilic leukemia cells (RBL) has beenwidely utilized in studies on leukotriene biosynthesis. Compounds thatinhibit 5-lipoxygenase decrease the levels of leukotrienes.

Another biological assay used to evaluate the ability of a compound toinhibit the enzyme 5-lipoxygenase is based on the classicpharmacological model of inflammation induced by inhibition of LTB₄ fromionophore stimulated human whole blood.

EXAMPLE 4 Ability of Compound to Bind to PAF Receptors

(a) Preparation of Human Platelet Membranes Human platelet membranes areprepared from platelet concentrates obtained from the American Red CrossBlood Services (Dedham, Mass.). After several washes with platelet washsolution (150 mM NaCl, 10 mM Tris, and 2 mM EDTA, pH 7.5), the plateletpellets are resuspended in 5 mM MgCl₂, 10 mM Tris, and 2 mM EDTA at pH7.0. The cells are then quickly frozen with liquid nitrogen and thawedslowly at room temperature. The freezing and thawing procedure isrepeated at least three times. For further fractionation of membranefragments, the lysed membrane suspension is layered over the top of adiscontinuous sucrose density gradient of 0.25, 1.03, and 1.5M sucroseprepared in 10 mM MgCl₂, 10 mM Tris and 2 mM EDTA, pH 7.0, andcentrifuged at 63,500×g for 2 hr. The membrane fractions banding between0.25 and 1.03M (membrane A) and between 1.03 and 1.5M (membrane B) arecollected separately. The protein concentration of the membranepreparations is determined by Lowry's method with bovine serum albumin(BSA) as the standard. The membranes are then separated into smallerfractions (4 ml each) and stored at -80° C. and thawed before use.

(b) ³ H!PAF Binding inhibition

The ability of ³ H!PAF to bind to specific receptors on human plateletmembranes is evaluated at optimal conditions at pH 7.0 and in thepresence of 10 mM MgCl₂. Membrane protein (100 μg) is added to a final0.5 ml solution containing 0.15 pmol (0.3 nM concentration) of ³ H!PAFand a known amount of unlabeled PAF or PAF receptor antagonist in 10 mMMgCl₂, 10 mM Tris and 0.25% BSA at pH 7.0. After incubation for fourhours at 0° C., the bound and unbound ³ H!PAF are separated through aWhatman GF/C glass fiber filter under vacuum. No degradation of filterbound ³ H!PAF should be detected under this assay condition. Thenonspecific binding is defined as the total binding in the presence ofexcess unlabeled PAF (1 mM) where no further displacement is found withhigher concentrations of either unlabeled PAF or PAF analogs or PAFreceptor antagonists. The specific binding is defined as the differencebetween total binding and nonspecific binding.

To determine the relative potency of tested compounds, ³ H!PAF bindingin the presence of inhibitors is normalized in terms of percentinhibition by assigning the total binding in the absence of inhibitorsas 0% inhibition and the total binding in the presence of 1 mM unlabeledPAF as 100%. The percent inhibition by the compound can be calculated bythe formula expressed below:

    % inhibition= (Total binding-total binding in the presence of compound)/nonspecific binding!×100%

The IC₅₀ is calculated as the concentration of the inhibitor necessaryto obtain 50% inhibition of the specific ³ H!PAF binding and iscalculated by a nonlinear regression computer software program, GraphPadInplot:, version 3.0 (GraphPad software, San Diego, Calif.).

EXAMPLE 5 Effect of Compound on PAF-induced Hemoconcentration

(a) Animals

Female CD-1 mice, weighing 16-20 grams, are obtained from Charles RiverLaboratory (Wilmington, Mass.). Tap water and rodent laboratory chow(5001, Purina Mills, St. Louis, Mo.) are provided ad libitum. The miceare housed for an average of four days prior to use.

(b) Hematocrit measurement

PAF (1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine, Sigma ChemicalCo.) is dissolved in 0.25% bovine serum albumin (BSA) in 0.9% NaClsolution. Except for dose-response studies, 10 μg (10 ml/kg) of PAFsolution is injected into the tail vein. All test compounds aredissolved in 0.5 DMSO saline solution and intravenously injected at 3mg/kg body weight 15 minutes prior to PAF challenge. Thirty to fifty μLblood is collected by cutting the tail end into a heparinizedmicro-hematocrit tube (O.D. 1.50 mm) 15 minutes after PAFadministration. All test compounds are given intravenously at 3 mg/kg 15minutes before PAF (10 ug/kg, intravenously) or AA (0.5 mg/ear) in mice.

EXAMPLE 6 Effect of Compounds on Cytosol 5-Lipoxygenase of Rat BasophileLeukemia Cells

(a) Enzyme preparation

Washed rat RBL cells (4x108) were suspended in 20 ml of 50M potassiumphosphate buffer at pH 7.4 containing 10% ethylene glycol/1 mM EDTA(Buffer A). The cell suspension was sonicated at 20 KHz for 30 seconds,and the sonicate was centrifuged at 10,000×g for 10 minutes, followed byfurther centrifugation at 105,000×g for 1 hr. The supernatant solution(cytosol fraction) containing 5-lipoxygenase was stored at -70° C.Protein concentration was determined according to the procedure ofBradford (Bradford Dye Reagent) with bovine serum albumin as a standard.

(b) Enzyme assay For routine assay of 5-lipoxygenase the mixturecontained 50 mM potassium phosphate buffer at pH 7.4, 2 mM CaCl₂, 2 mMATP, 25M arachidonic acid (0.1 Ci) and enzyme (50-100 mg of protein) ina final volume of 200 L. The reaction was carried out at 24° C. for 3minutes. The mixture was extracted with 0.2 ml of an ice-cold mixture ofethyl ether:methanol: 0.2M citric acid (30:4:1). The extract wassubjected to thin-layer chromatography at -10° C. in a solvent system ofpetroleum ether:ethyl ether:acetic acid (15:85:0.1). The silica gelzones corresponding to authentic arachidonic acid and its metaboliteswere scraped into scintillation vials for counting. The enzyme activitywas expressed in terms of the amount of arachidonic acid oxygenated for3 minutes. Representative compounds 9, 11, 14, and 15, identified above,showed activity in this assay.

Modifications and variations of the present invention relating tocompounds that reduce the formation of oxygen radicals during aninflammatory or immune response will be obvious to those skilled in theart from the foregoing detailed description of the invention. Suchmodifications and variations are intended to come within the scope ofthe appended claims.

We claim:
 1. A compound of formula: ##STR25## wherein: Ar is an aryl orheteroaryl group that is optionally substituted with at least one groupselected from the group consisting of halo, lower alkoxy, lower aryloxy,--C(O)N(OM)R⁴, A--B, cyano, or R³ ; but when W is --A--B, Ar issubstituted at least once with --C(O)N(OM)R⁴, and is optionallysubstituted with halo, lower alkoxy, lower aryloxy, A--B, cyano, or R³;W is independently --C(O)N(OM)R⁴, or --A--B; but when W is --A--B, Aris substituted at least once with --C(O)N(OM)R⁴, and is optionallysubstituted with halo, lower alkoxy, lower aryloxy, A--B, cyano, or R³ ;A is lower alkyl, lower alkenyl, lower alkynyl, alkaryl or aralkylgroups, wherein one or more carbons optionally can be replaced by O, N,or S; (with valence completed with hydrogen or oxygen as necessary),provided --A-- does not form two adjacent heteroatoms; B is selectedfrom the group consisting of pyridylimidazole and benzimidazole, eitherof which is optionally substituted with R₃ ; M is hydrogen, apharmaceutically acceptable cation, or a metabolically cleavable leavinggroup; X is O, S, S(O), NR⁵, or CHR⁵ ; R¹ and R² are independentlyhydrogen, lower alkyl; halo lower alkyl, halo; and --COOH; and R³ and R⁴are independently hydrogen or alkyl, alkenyl, alkynyl, aryl, aralkyl,alkaryl, C₁₋₆ alkoxy-C₁₋₁₀ alkyl, C₁₋₆ alkylthio-C₁₋₁₀ alkyl,heteroaryl, or heteroarylalkyl-; R⁵ is hydrogen, lower alkyl, loweralkenyl, lower alkynyl, alkaryl, --AN(OM)C(O)N(R³)R⁴,--AN(R³)C(O)N(OM)R⁴, --AN(OM)C(O)R⁴, --AC(O)N(OM)R⁴, --AS(O)_(n) R³,--AS(O)_(n) CH₂ C(O)R³, --AS(O)_(n) CH₂ CH(OH)R³, --AC(O)NHR³ ; andwherein n is 0-2,or pharmaceutically acceptable salt thereof.
 2. Thecompound of claim 1, wherein Ar is selected from the group consisting ofphenyl, trimethoxyphenyl, dimethoxyphenyl, fluorophenyl, difluorophenyl,pyridyl, dimethoxypyridyl, quinolinyl, furyl, imidazolyl, and thienyl.3. The compound of claim 1, wherein Ar is selected from the groupconsisting of 4-fluorophenyl, 3,4,5-trimethoxyphenyl,3,4-dimethoxyphenyl, 2,3-dimethoxypyridyl, 3,4-difluorophenyl,3-quinolinyl,wherein: R¹ and R² are hydrogen.
 4. A pharmaceuticalcomposition comprising an effective amount of the compound of claim 1,or a pharmaceutically acceptable salt thereof, and a pharmaceuticallyacceptable carrier.
 5. A method for the treatment of inflammatorydisorders in a host comprising administering an effective amount of acompound of claim 1 or a pharmaceutically acceptable salt thereof. 6.The method of claim 5, wherein the animal is selected from a human, amammal, an equine, a canine and a bovine.
 7. The compound of claim 1wherein X is O.
 8. The compound of claim 1, wherein the aryl group has ahalogen substituent.
 9. The compound of claim 1 wherein W is --A--B .10. The compound of claim 9, wherein R³ or R⁴ are hydrogen.
 11. Thecompound of claim 1, wherein R¹ and R² are hydrogen.
 12. The compound ofclaim 1, wherein A is selected from the group consisting of acetylenyl,propynyl, and --C.tbd.C--CH(alkyl)-.
 13. The compound of claim 1,wherein A is lower alkyl-.
 14. The compound of claim 1 wherein X is S.15. The compound of claim 1 wherein the aryl group has a fluorinesubstituent.
 16. The compound of claim 1, wherein W is --C(O)N(OM)R⁴.17. The compound of claim 1, wherein A is lower alkenyl.
 18. Thecompound of claim 1, wherein A is lower alkynyl.
 19. The compound ofclaim 1, wherein B is benzimidazole.
 20. The method of claim 5, whereinthe compound has a W substituent that is --A--B.
 21. A compound offormula: ##STR26## wherein: Ar is an aryl or heteroaryl group any ofwhich is substituted at least once with --C(O)N(OM)R⁴, and is optionallysubstituted with halo, lower alkoxy, lower aryloxy, A--B, cyano, or R³;A is lower alkyl, lower alkenyl, lower alkynyl, alkaryl or aralkylgroups, wherein one or more carbons optionally can be replaced by O, N,or S; (with valence completed with hydrogen or oxygen as necessary),provided --A-- does not form two adjacent heteroatoms; B is selectedfrom the group consisting of pyridylimidazole and benzimidazole, eitherof which is optionally substituted with R₃ ; M is hydrogen, apharmaceutically acceptable cation, or a metabolically cleavable leavinggroup; X is O, S, S(O); R¹ and R² are independently hydrogen, loweralkyl; halo lower alkyl; halo; and --COOH; and R³ and R⁴ areindependently hydrogen or alkyl, alkenyl, alkynyl, aryl, aralkyl,alkaryl, C₁₋₆ alkoxy-C₁₋₁₀ alkyl, C₁₋₆ alkylthio-C₁₋₁₀ alkyl,heteroaryl, or heteroarylalkyl;or pharmaceutically acceptable saltthereof.
 22. The compound of claim 21 wherein --A--B is ##STR27## andwherein Ar is aryl or heteroaryl, any of which group is substituted atleast once with--C(O)N(OM)R⁴, and is optionally substituted with halo,alkoxy, aryloxy, or cyano.
 23. The compound of claim 21, wherein --A--Bis ##STR28## and wherein Ar is aryl or heteroaryl substituted at leastonce --C(O)N(OM)R⁴.
 24. A pharmaceutical composition comprising aneffective amount of the compound of claim 21 or a pharmaceuticallyacceptable salt thereof, and a pharmaceutically acceptable carrier. 25.A pharmaceutical composition comprising an effective amount of thecompound of claim 23 or a pharmaceutically acceptable salt thereof, anda pharmaceutically acceptable carrier.
 26. A method for the treatment ofinflammatory disorders in a host comprising administering an effectiveamount of a compound of claim 21 or a pharmaceutically acceptable saltthereof.
 27. A method for the treatment of inflammatory disorders in ahost comprising administering an effective amount of a compound of claim22 or a pharmaceutically acceptable salt thereof.
 28. A method for thetreatment of inflammatory disorders in a host comprising administeringan effective amount of a compound of claim 23 or a pharmaceuticallyacceptable salt thereof.
 29. A method for the treatment of inflammatorydisorders in a host comprising administering an effective amount of acompound of any of claims 7-10, or 12-19, or a pharmaceuticallyacceptable salt thereof.
 30. A method for the treatment of inflammatorydisorders in a host comprising administering an effective amount of acompound of claim 21 or a pharmaceutically acceptable salt thereof.